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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: Crashes trying to use QtAgg backend","articleBody":"### Bug summary\n\nI tried doing `pip install pyside6` and using matplotlib and a chart window appears, but just hangs.\r\n\r\n\n\n### Code for reproduction\n\n```python\nimport matplotlib as mpl\r\nimport matplotlib.pyplot as plt\r\n\r\nmpl.use('QtAgg') # 'QT5Agg' also fails, 'TkAgg' works.\r\n\r\nplt.plot([1, 2, 3, 2, 3, 4])\r\n\r\nplt.show()\n```\n\n\n### Actual outcome\n\nChart window opens and hangs.\r\n\r\n![image](https://user-images.githubusercontent.com/4443482/170164529-43fc5742-5d12-4513-a1eb-5078be95fd00.png)\r\n\n\n### Expected outcome\n\nShould work the same as when the backend is `TkAgg`.\r\n\n\n### Additional information\n\nI'm running the code in IntelliJ and everything worked fine before I installed Qt.\r\n\r\nI'm a newbie and a bit confused as to what exactly I need to do to use Qt as a backend. Note that I'm just exploring/learning, I don't have a _reason_ to want to use Qt over Tk or anything else.\r\n\r\nI've read [this page on Qt bindings](https://github.com/matplotlib/matplotlib/blob/96ddc6728ce09cb61f6b6c53714755fe0936b106/doc/api/backend_qt_api.rst) (the text on this page doesn't show up in the actual docs)\r\n\r\nAnd also saw https://github.com/matplotlib/matplotlib/pull/19255 that seems to add support and was merged and I'm using a later version `3.5.2`.\r\n\r\nAnd I've read [this page in the docs](https://matplotlib.org/3.5.0/users/explain/backends.html#how-do-i-select-the-qt-implementation) and it seems to imply (but not say) that all I need to do is install PySide6 and it should work.\r\n\r\nWeirdly, if I just use the code:\r\n```py\r\nimport matplotlib.pyplot as plt\r\n\r\nplt.plot([1, 2, 3, 2, 3, 4])\r\n\r\nplt.show()\r\n```\r\nIt works, which is weird for two reasons:\r\n1. This means that just _importing matplotlib_ invokes different behaviour to importing `matplotlib.pyplot`.\r\n2. Not importing matplotlib directly (only `pyplot`) results in the message \"Backend MacOSX is interactive backend. Turning interactive mode on.\". Weird as I'm on Windows, and if I then run `plt.get_backend()` it says `QtAgg`. It's all so confusing!\n\n### Operating system\n\nWindows 11\n\n### Matplotlib Version\n\n3.5.2\n\n### Matplotlib Backend\n\nQtAgg, Qt5Agg\n\n### Python version\n\n3.10.2\n\n### Jupyter version\n\n_No response_\n\n### Installation\n\npip","author":{"url":"https://github.com/davidgilbertson","@type":"Person","name":"davidgilbertson"},"datePublished":"2022-05-25T02:27:37.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":6},"url":"https://github.com/23131/matplotlib/issues/23131"}